Clinically-staged T3N0 rectal cancer: is preoperative chemoradiotherapy the optimal treatment?

Predictive Study of Machine Learning-Based Multiparametric MRI Radiomics Nomogram for Perineural Invasion in Rectal Cancer: A Pilot Study

This study aimed to establish and validate the efficacy of a nomogram model, synthesized through the integration of multi-parametric magnetic resonance radiomics and clinical risk factors, for forecasting perineural invasion in rectal cancer. We retrospectively collected data from 108 patients with pathologically confirmed rectal adenocarcinoma who underwent preoperative multiparametric MRI at the First Affiliated Hospital of Bengbu Medical College between April 2019 and August 2023. This dataset was subsequently divided into training and validation sets following a ratio of 7:3. Both univariate and multivariate logistic regression analyses were implemented to identify independent clinical risk factors associated with perineural invasion (PNI) in rectal cancer. We manually delineated the region of interest (ROI) layer-by-layer on T2-weighted imaging (T2WI) and diffusion-weighted imaging (DWI) sequences and extracted the image features. Five machine learning algorithms were used to construct radiomics model with the features selected by least absolute shrinkage and selection operator (LASSO) method. The optimal radiomics model was then selected and combined with clinical features to formulate a nomogram model. The model performance was evaluated using receiver operating characteristic (ROC) curve analysis, and its clinical value was assessed via decision curve analysis (DCA). Our final selection comprised 10 optimal radiological features and the SVM model showcased superior predictive efficiency and robustness among the five classifiers. The area under the curve (AUC) values of the nomogram model were 0.945 (0.899, 0.991) and 0.846 (0.703, 0.99) for the training and validation sets, respectively. The nomogram model developed in this study exhibited excellent predictive performance in foretelling PNI of rectal cancer, thereby offering valuable guidance for clinical decision-making. The nomogram could predict the perineural invasion status of rectal cancer in early stage.

How We Treat Localized Rectal Cancer-An Institutional Paradigm for Total Neoadjuvant Therapy

Total neoadjuvant therapy (TNT)-the neoadjuvant employment of radiotherapy (RT) or chemoradiation (CRT) as well as chemotherapy (CHT) before surgery-may lead to increased pathological complete response (pCR) rates as well as a reduction in the risk of distant metastases in locally advanced rectal cancer. Furthermore, increased response rates may allow organ-sparing strategies in a growing number of patients with low rectal cancer and upfront immunotherapy has shown very promising early results in patients with microsatellite instability (MSI)-high/mismatch-repair-deficient (dMMR) tumors. Despite the lack of a generally accepted treatment standard, we strongly believe that existing data is sufficient to adopt the concept of TNT and immunotherapy in clinical practice. The treatment algorithm presented in the following is based on our interpretation of the current data and should serve as a practical guide for treating physicians-without any claim to general validity.

Radiomics for predicting perineural invasion status in rectal cancer

BACKGROUND

Perineural invasion (PNI), as a key pathological feature of tumor spread, has emerged as an independent prognostic factor in patients with rectal cancer (RC). The preoperative stratification of RC patients according to PNI status is beneficial for individualized treatment and improved prognosis. However, the preoperative evaluation of PNI status is still challenging.

AIM

To establish a radiomics model for evaluating PNI status preoperatively in RC patients.

METHODS

This retrospective study enrolled 303 RC patients in a single institution from March 2018 to October 2019. These patients were classified as the training cohort (n = 242) and validation cohort (n = 61) at a ratio of 8:2. A large number of intra- and peritumoral radiomics features were extracted from portal venous phase images of computed tomography (CT). After deleting redundant features, we tested different feature selection (n = 6) and machine-learning (n = 14) methods to form 84 classifiers. The best performing classifier was then selected to establish Rad-score. Finally, the clinicoradiological model (combined model) was developed by combining Rad-score with clinical factors. These models for predicting PNI were compared using receiver operating characteristic curve (ROC) analysis and area under the ROC curve (AUC).

RESULTS

One hundred and forty-four of the 303 patients were eventually found to be PNI-positive. Clinical factors including CT-reported T stage (cT), N stage (cN), and carcinoembryonic antigen (CEA) level were independent risk factors for predicting PNI preoperatively. We established Rad-score by logistic regression analysis after selecting features with the L1-based method. The combined model was developed by combining Rad-score with cT, cN, and CEA. The combined model showed good performance to predict PNI status, with an AUC of 0.828 [95% confidence interval (CI): 0.774-0.873] in the training cohort and 0.801 (95%CI: 0.679-0.892) in the validation cohort. For comparison of the models, the combined model achieved a higher AUC than the clinical model (cT + cN + CEA) achieved (P < 0.001 in the training cohort, and P = 0.045 in the validation cohort).

CONCLUSION

The combined model incorporating Rad-score and clinical factors can provide an individualized evaluation of PNI status and help clinicians guide individualized treatment of RC patients.

Prognostic Importance of MRI-Detected Extramural Venous Invasion in Rectal Cancer: A Literature Review and Systematic Meta-Analysis

PURPOSE

Extramural venous invasion (EMVI) is recognized as a poor prognostic factor in rectal cancer. There are well-documented limitations associated with pathology detection of EMVI, including variable reporting and the inability to use it preoperatively to guide neoadjuvant treatment. Magnetic resonance imaging (MRI)-detected EMVI (mrEMVI) has been proposed as an imaging biomarker. This review assesses the prognostic significance of mrEMVI on survival outcomes and whether regression of mrEMVI after neoadjuvant therapy is associated with improvements in survival.

METHODS AND MATERIALS

An electronic search was carried out using MEDLINE and EMBASE databases using the search terms "rectum," "cancer,", "MRI," and "outcomes." A systematic review and meta-analysis were carried out in accordance with Preferred Reporting for Systematic Reviews and Meta-Analyses guidelines using Review Manager software. A qualitative review was performed.

RESULTS

A total of 7399 articles were identified, of which 33 were relevant to the review question. After a qualitative assessment, 20 articles were included in the meta-analysis. Baseline mrEMVI positivity is associated with significantly worsened overall survival (hazard ratio [HR] 1.84; 95% confidence interval [CI], 1.33-2.54; P = .0001) and significantly worsened disease-free survival (HR 2.41; 95% CI, 2.02-2.89; P < .00001). After neoadjuvant treatment, a positive mrEMVI status is associated with a significantly worsened overall and disease-free survival. Only 3 papers specifically looked at mrEMVI regression, but the results show that persistent mrEMVI-positive status after treatment is associated with significantly worsened disease-free survival compared with a change in mrEMVI from positive to negative (HR 1.93; 95% CI, 1.39-2.68; P < .0001). A subgroup analysis of MRI-detected lymph node metastases showed no significant association with survival, with a hazard ratio of 1.33 (95% CI, 0.98-1.80; P = .06).

CONCLUSION

mrEMVI is significantly associated with worsened survival outcomes, both at baseline and after neoadjuvant treatment. Additionally, there is evidence that regression of mrEMVI after neoadjuvant treatment is associated with improved survival compared with mrEMVI persistence. The findings of this review emphasize the need for accurate and consistent reporting of mrEMVI status before and after neoadjuvant treatment and support the inclusion of mrEMVI into staging systems preferentially over lymph node metastases.

Clinical staging accuracy and the use of neoadjuvant chemoradiotherapy for cT3N0 rectal cancer: Propensity score matched National Cancer Database analysis

BACKGROUND

While neoadjuvant chemoradiation therapy (nCRT) is accepted as standard of care for locally advanced rectal cancer, the approach to treatment of patients with clinically staged T3N0 disease has been increasingly debated. This study examines the accuracy of clinical staging for cT3N0 rectal cancer as recorded in the National Cancer Data Base and evaluates the role of nCRT in treating these patients.

METHODS

Total of 15,843 patients with clinically staged T3N0M0 rectal cancer who either received nCRT or proceeded to surgery-first met inclusion criteria. Propensity score matching was employed to balance the groups.

RESULTS

23% of cT3N0 patients undergoing surgery-first were found to have pathologically positive nodes. Another 16% turned out to have < stage II disease on surgical pathology. Survival curves for matched nCRT and surgery-first groups demonstrated a survival advantage for cT3N0 patients treated with nCRT.

CONCLUSIONS

Poor clinical staging accuracy can result in both undertreatment and overtreatment of cT3N0 rectal cancer.

Patterns of care and outcomes for adjuvant treatment of pT3N0 rectal cancer using the National Cancer Database

Background

The standard of care in locally advanced rectal cancer is preoperative chemoradiation followed by surgical resection. However, the optimal treatment paradigm is currently controversial for patients with pathological T3N0 (pT3N0) in the era of total mesorectal excision (TME). Given the paucity of data, we conducted an analysis using the National Cancer Database (NCDB) to identify patterns of care and outcomes.

Methods

We utilized the NCDB to identify 7,836 non-metastatic, pT3N0 rectal cancer patients who did not receive neoadjuvant therapy from 2004-2014. Univariate and multivariable analysis for factors affecting treatment selection were completed using logistic regression. Overall survival (OS) analyses were completed using Cox regression modeling, incorporating propensity scores with inverse probability of treatment weighting (IPTW) and conditional landmark analysis.

Results

There was a significant improvement in OS in patients receiving adjuvant chemotherapy (P<0.01) or radiotherapy (RT) with chemotherapy (P<0.01) vs. observation alone. There was no significant difference between RT vs. observation (P=0.54) and chemotherapy vs. chemotherapy with RT cohorts (P=0.15). Multivariable analysis showed age, gender, race, insurance status, income, Charlson-Deyo Comorbidity Condition (CDCC) score, facility location, grade, surgical margin, RT, and chemotherapy to be statistically significant predictors of OS. After correcting for indication and immortal time biases, chemotherapy, with or without RT, improved OS compared with observation [hazard ratio (HR) 0.48, P<0.001]. This benefit was maintained in the margin negative cohort.

Conclusions

Practice patterns vary in the management of pT3N0 rectal cancer patients. This analysis suggests that the use of adjuvant therapy, particularly adjuvant chemotherapy with or without RT, appears to improve OS.

Neoadjuvant chemoradiation improves oncologic outcomes in low and mid clinical T3N0 rectal cancers

BACKGROUND

Controversial data exists in the current literature in regard to the use of neoadjuvant chemoradiation (nCRT) in patients with clinical T3N0 (cT3N0) rectal cancers, specifically based on location and relation to peritoneal reflection. We aimed to analyze the impact of nCRT on oncologic outcomes among cT3N0 rectal cancers, depending on the tumor height from anal verge (AV).

METHODS

A retrospective analysis of patients with cT3N0 rectal cancers was included from a query of a prospectively maintained rectal cancer database from 1980 to 2016. Patients were divided into 3 groups based on the tumor height: low (1-5 cm from AV), mid (6-10 cm from AV), and upper (11-15 cm from AV). Patients were stratified by use of nCRT.

MAIN OUTCOMES

5-year overall survival (OS), disease-free survival (DFS), cancer-specific survival (CSS), and local recurrence (LR) using Kaplan-Meier curves.

RESULTS

Five hundred ninety-two patients were included. Overall, 364 (61.4%) patients received nCRT and 228 (38.6%) patients did not. There were 251 (43%) patients with low, 302 (51%) with mid, and 39 (7%) with upper rectal cancer. Patients with low and mid rectal cancers received nCRT more frequently than those with upper rectal cancers (68.5% and 61.2% vs 43.6%, p = 0.007). The 5-year OS was 78% and 63%, DFS-88% and 73%, LR-1% and 8% in nCRT followed by resection vs. surgery alone (p < 0.001). In regard to cancer location after nCRT compared with surgery alone, low and mid cancers had better OS, DFS, and CSS, compared with upper ones.

CONCLUSION

nCRT prolongs survival among patients with rectal cancer below 10 cm from AV; however, it has no effect on 5-year oncologic survival of patients with upper rectal cancer located below peritoneal reflection.

Does one size fit all? Risks and benefits of neoadjuvant chemoradiation in patients with clinical stage IIA rectal cancer requiring abdominoperineal resection

BACKGROUND

Neoadjuvant chemoradiotherapy (nCRT) has become the standard of care for locally advanced rectal cancer, decreasing locoregional recurrence, yet with an unclear survival advantage. We aimed to assess the benefit of nCRT on oncologic and perioperative outcomes of patients with clinical stage IIA rectal adenocarcinoma treated with abdominoperineal resection (APR).

METHODS

Patients with clinical T3N0 rectal adenocarcinoma that underwent APR between 1995 and 2014 were included. Patients who received nCRT were compared with patients who did not. Multivariate analysis was conducted to compare oncological and perioperative outcomes between the groups.

RESULTS

127 patients were included, of which 94 received nCRT. Median follow-up was 11.9 years. There was no difference in circumferential margins, postoperative morbidity, and complication rates between the groups. There was no difference in 5-year oncological outcomes between the groups.

CONCLUSIONS

No difference was found in 5-year oncological outcomes between patients with clinical T3N0 rectal adenocarcinoma necessitating an APR who received nCRT and those not receiving nCRT, with similar overall complication rates.

The risk of nodal disease in patients with pathological complete responses after neoadjuvant chemoradiation for rectal cancer: a systematic review, meta-analysis, and meta-regression

BACKGROUND

This systematic review and meta-analysis seek to evaluate the prevalence of nodal disease in rectal cancer patients with pathological complete responses (pCR) after neoadjuvant chemoradiotherapy (ypT0N+).

METHODS

This study conformed to the PRISMA guidelines. A search was performed on major databases to identify relevant articles. Meta-analyses of pooled proportions were performed on rectal cancer with pCR and ypT0N+. Meta-regression was undertaken to identify sources of heterogeneity, and the Newcastle-Ottawa Scale (NOS) was employed to assess the risk of bias.

RESULTS

A total of 18 studies were included, totaling 7568 patients. The overall risk of bias was low, since all studies scored 6 and above out of 9 on the NOS. Preoperatively, the pooled proportions of patients with T3/T4 tumors and clinically positive nodal disease were 84.08% (95% CI 74.19 to 91.99%) and 52.14% (95% CI 35.02 to 69.00%) respectively. The prevalence of pCR in the whole pool was 18.52% (95% CI 13.31 to 24.35%; I² = 93.85%; P = 0.00), and meta-regression showed a significantly negative relationship with patient age (β = - 0.03, 95% CI - 0.03 to - 0.02; P = 0.00). The pooled prevalence of ypT0N+ was 4.61% (95% CI 2.41 to 7.28%; I² = 52.27%; P = 0.01), and meta-regression demonstrated a significantly positive relationship with male gender (β = 1.06, 95% CI 1.00 to 1.12; P = 0.04).

CONCLUSION

There is a small risk of ypN+ in patients with pCR after neoadjuvant CRT and surgery for rectal cancer. However, further research is warranted to establish these findings and to identify predictive factors for this specific group of patients.

Comparative Outcomes of Preoperative Chemoradiotherapy and Selective Postoperative Chemoradiotherapy in Clinical Stage T3N0 Low and Mid Rectal Cancer

Purpose/aim: Preoperative chemoradiotherapy (pre-CRT) and total mesorectal excision (TME) have become the standard of care for patients with locally advanced rectal cancer (LARC). Nevertheless, it is a controversial issue whether pre-CRT in cT3N0M0 patients would result in potential overtreatment. Materials and methods: In total, 183 clinical stage IIA rectal cancer patients treated with and without pre-CRT between 2011 and 2014 were retrospectively analyzed. Capecitabine/FOLFOX/CAPOX chemotherapy was co-administered with preoperative radiotherapy. Surgical resection with laparoscopic or open TME was conducted 8-12 weeks after completion of the pre-CRT. Postoperative radiotherapy was routinely given to patients with pT4 lesion or circumferential margin (CRM) and/or distal resection margin (DRM) involvement. Results: In total, 108 (59%) patients received pre-CRT and 75 (41%) underwent surgery first. The pre-CRT patients presented with less-advanced pathological T stage tumors compared with the surgery-first patients (p < 0.001). However, the pathological N stage was not significantly different between the two groups (p = 0.065). The 3-year overall survival (OS), disease-free survival (DFS), and 2-year local recurrence (LR) rate were similar in the pre-CRT and surgery-first patients (88.4 versus 88.7%, p = 0.552; 79.6 versus 83.3%, p = 0.797; 2.8 versus 2.7%, p = 0.960, respectively). Cox regression analysis showed that pN stage and CRM/DRM involvement were independently correlated with an unfavorable DFS. Conclusions: In this study, the omission of pre-CRT in cT3N0M0 patients did not translate into a worse oncological outcome. Postoperative radiotherapy should remain a standard option for patients with CRM/DRM involvement and pathological T4 tumors. A generalized indication for pre-CRT in cT3N0 patients is likely to result in overtreatment.

Radiotherapy for stage IIA rectal cancer may not benefit all

This study sought to determine whether additional radiotherapy is necessary in patients after optimal surgery for stage IIA rectal cancer and how the different covariates influence the efficacy of radiotherapy. The first primary rectal cancer was identified from the 1988–December 2013 Surveillance, Epidemiology and End Results database. We identified 13647 patients with IIA rectal cancer, in which 39.6% received neo-adjuvant radiotherapy and in another 14.96% patients the adjuvant radiotherapy were performed. Neo-adjuvant or adjuvant radiotherapy group had better survival with 10-Year cancer-specific survival estimates as 75.1% and 73.8% compared to 68.4% of no radiotherapy group (P < 0.01). Adjusted hazard ratio (HR) demonstrated neo-adjuvant and adjuvant radiotherapy (HR: 0.814 and 0.848) were all associated with significantly decreased risk for cancer death. However, radiotherapy did not seem to yield the same survival benefit in selected population. Adjusted stratified analysis demonstrated patients with increasing age, relative large tumor size, and more retrieved regional lymph nodes had no additional benefit for cancer specific survival based on radiation use. In conclusions, unselected patients with stage IIA rectal cancer receiving radiotherapy experienced better survival in comparison to patients without radiation. However, additional radiotherapy is not beneficial for all.

Extramural perineural invasion in pT3 and pT4 rectal adenocarcinoma as prognostic factor after preoperative chemoradiotherapy

Perineural invasion (PNI) is widely studied in malignant tumors, and its prognostic significance is well demonstrated in the head and neck and prostate carcinomas, but its significance in rectal cancer is controversial. Most studies have focused on evaluating mural PNI (mPNI); however, extramural PNI (ePNI) may influence the prognosis after rectal cancer resection. We evaluated the prognostic value of ePNI compared with mPNI and with non-PNI, in rectal resections after preoperative chemoradiotherapy in 148 patients with pT3 and pT4 rectal carcinomas. PNI was identified in 35 patients (23.6%), 60% of which were in the mPNI group. Factors associated with PNI were tumor invasion depth, lymph node metastasis, lymphovascular invasion, and venous invasion; patients with PNI were more likely to have positive resection margins (65.7% versus 11.6%). ePNI, compared with mPNI, was associated with female sex (64.3% versus 28.6%), positive surgical margins (42.8% versus 28.6%), recurrence (50% versus 28.6%), and death (92.9% versus 28.6%). The 5-year disease-specific survival rate was 78.1% for patients without PNI, compared with 63.7% for the mPNI group and 26.4% for the ePNI group (P<.001). On multivariate analysis, the independent adverse prognostic factors were ePNI (odds ratio [OR], 22.17; 95% confidence interval [CI], 17.03-24.58; P<.001), overall recurrence (OR, 9.19; CI, 6.11-10.63; P=.002), clinical stage IV (OR, 8.56; CI, 6.34-9.47; P=.003), and positive surgical margin (OR, 3.95; CI, 2.00-4.28; P=.047). In conclusion, we demonstrated the prognostic effect of ePNI for disease-specific survival in surgically resected pT3-pT4 rectal cancer patients with preoperative chemoradiotherapy.

Kinetically guided neoadjuvant chemoradiotherapy based on 5-Fluorouracil in patients with locally advanced rectal cancer

BACKGROUND AND PURPOSE

This study estimated patients' early response following neoadjuvant chemoradiotherapy (CHRT) of locally advanced rectal cancer based on 5-fluorouracil (5-FU). The target was to achieve pathological complete response (pCR; residual disease-free stage) and toxicities of grade ≤2, using individual dosing predicted according to the steady-state plasma concentration (C ss) and pharmacokinetic parameters of 5-FU: the area under the time-concentration curve at steady state (AUC) and clearance (CL).

PATIENTS AND METHODS

This open-label prospective study enrolled 33 adult patients treated with 5-FU administered as a continuous intravenous infusion over 4-5 weeks, as follows: in Group 1a (N = 6), the patients received a standard dose of 300 mg/m(2)/24 h. In Group 1b (N = 7), the patients were treated with an escalated dose of 400-1,000 mg/m(2)/24 h. In Group 2 (N = 20), the patients were given dosing kinetically guided in order to reach the target range of 5-FU C ss 50-100 µg/L. Tolerability was tested according to Common Terminology Criteria for Adverse Events v3.0 (CTCAE). Radiotherapy was delivered with 10-15 MV photon beams at 1.8 Gy/fraction up to 50.4 Gy in 28 daily fractions for 5 days a week. Surgery followed 4-6 weeks after the completion of CHRT and clinical restaging. The pCR and residual tumour stage were evaluated using preoperative tumour downstaging in magnetic resonance, postoperative histopathological staging and tumour regression rate (residual disease).

RESULTS AND CONCLUSION

The cumulative AUC of 5-FU (total exposure to the drug) correlated with cumulative 5-FU dose (r = 0.61; p < 0.001) and residual disease (r s = -0.53; p < 0.005). A higher target pCR rate was reached in patients individually treated (Group 2) who finished the whole 5-week CHRT. The individual daily dose needed to reach the target C ss should be >350 mg/m(2) (up to 600 mg/m(2)) provided that 5-FU metabolic ratio is within the range of 2.5-6 and the cumulative AUC5wks is within 50-100 mg·h/L.

Preoperative chemoradiotherapy for clinically diagnosed T3N0 rectal cancer

PURPOSE

This retrospective study compared the recurrence-free survival (RFS) and local recurrence rates of patients who received preoperative chemoradiotherapy (PCRT) for cT3N0 vs. those who did not.

METHODS

We analyzed the records of 593 patients with transrectal ultrasound (TUS) or magnetic resonance image (MRI)-staged cT3N0 mid and low locally advanced rectal cancer, including 255 who received PCRT and 338 who did not. The RFS and cumulative local recurrence rates were compared in the two groups. We also investigated the rates of pathologic complete response (pCR) and mesorectal lymph node (LN) involvement in the PCRT group.

RESULTS

The overall pCR rate was 13.3 %. Of the 338 non-PCRT patients, 125 (37.0 %) had pathologically positive mesorectal LNs. Sphincter-preserving surgery was performed in 431 (72.7 %) of the 593 patients, with similar rates in the two groups. However, the sphincter preservation rate in patients with low rectal cancer was higher among those who received PCRT than among those who did not (64.8 vs. 47 %, P = 0.002). The 5-year RFS (76.4 vs. 75.5 %, P = 0.92) and local recurrence (3.9 vs. 3.0 %, P = 0.97) rates were similar in the PCRT and non-PCRT groups.

CONCLUSION

Although PCRT did not improve the RFS or local recurrence rates, it increased the chance of sphincter preservation in patients with low rectal cancer. The advantages of PCRT for patients with cT3N0 should be re-evaluated considering the limitation of pretreatment staging, oncologic benefits, and improved sphincter preservation.

Intermittent clamping of the hepatic pedicle in simultaneous ultrasonography-guided liver resection and colorectal resection with intestinal anastomosis: is it safe?

PURPOSE

In patients with colorectal cancer (CRC) and synchronous colorectal liver metastases (CRLM) potentially candidates to combined liver (LR) and colorectal resection (CRR), the extent of LR and the need of hepatic pedicle clamping (HPC) in selected cases are considered risk factors for the outcome of the intestinal anastomosis. This study aimed to determine whether intermittent HPC is predictive of anastomotic leakage (AL) and has an adverse effect on the clinical outcome in patients undergoing combined restorative CRR and LR.

METHODS

One hundred six LR have been performed for CRLM in our unit from July 2005. Patients who received CRR with anastomosis and simultaneous intraoperative ultrasonography (IOUS)-guided LR/ablation for resectable CRLM were included in this study. CRR was performed first. Intermittent HPC was decided at the discretion of the liver surgeon. The perioperative outcome was evaluated according to occurrence of AL and overall postoperative morbidity and mortality.

RESULTS

Thirty-eight patients underwent simultaneous IOUS-guided LR/ablation and CRR with intestinal anastomosis; 19 underwent intermittent HPC (group ICHPY) while 19 did not (group ICHPN); the mean ± SD (range) duration of clamping in group ICHPY was 58.6 ± 32.2 (10.0-125.0) min. Postoperative results were similar between groups. One asymptomatic AL occurred in group ICHPY (5.2 %). Major postoperative complications were none in group ICHPY and one (5.2 %) in group ICHPN, respectively. One patient in group ICHPY died postoperatively (5.2 %).

CONCLUSIONS

This study suggests that intermittent HPC during LR is not predictive of AL and has no adverse effect on the overall clinical outcome in patients undergoing combined restorative colorectal surgery and hepatectomy for advanced CRC.

A systematic review of outcome reporting in colorectal cancer surgery

AIM

Evaluation of surgery for colorectal cancer (CRC) is necessary to inform clinical decision-making and healthcare policy. The standards of outcome reporting after CRC surgery have not previously been considered.

METHOD

Systematic literature searches identified randomized and nonrandomized prospective studies reporting clinical outcomes of CRC surgery. Outcomes were listed verbatim, categorized into broad groups (outcome domains) and examined for a definition (an appropriate textual explanation or a supporting citation). Outcome reporting was considered inconsistent if results of the outcome specified in the methods were not reported. Outcome reporting was compared between randomized and nonrandomized studies.

RESULTS

Of 5644 abstracts, 194 articles (34 randomized and 160 nonrandomized studies) were included reporting 766 different clinical outcomes, categorized into seven domains. A mean of 14 ± 8 individual outcomes were reported per study. 'Anastomotic leak', 'overall survival' and 'wound infection' were the three most frequently reported outcomes in 72, 60 and 44 (37.1%, 30.9% and 22.7%) studies, respectively, and no single outcome was reported in every publication. Outcome definitions were significantly more often provided in randomized studies than in nonrandomized studies (19.0% vs 14.9%, P = 0.015). One-hundred and twenty-seven (65.5%) papers reported results of all outcomes specified in the methods (randomized studies, n = 21, 61.5%; nonrandomized studies, n = 106, 66.2%; P = 0.617).

CONCLUSION

Outcome reporting in CRC surgery lacks consistency and method. Improved standards of outcome measurement are recommended to permit data synthesis and transparent cross-study comparisons.

Preoperative versus postoperative chemoradiotherapy in stage T3, N0 rectal cancer

BACKGROUND

The study populations of previous preoperative chemoradiotherapy (pre-CRT) studies have consisted of mixed clinical stages, such as cT3-cT4 and/or cN positive. For this reason, it has not been possible to demonstrate whether pre-CRT is of benefit for individual subgroups.

METHODS

The medical records of 137 rectal cancer patients with clinical stage T3, N0 disease who received either pre-CRT or postoperative chemoradiotherapy (post-CRT) between 2002 and 2011 were retrospectively analyzed. The regimen of pre-CRT consisted of slow fluorouracil (5FU) infusion and that of post-CRT consisted of bolus 5FU and leucovorin concurrent with radiation.

RESULTS

Following pre-CRT, significant downstaging was achieved. However, administration of pre-CRT did not influence the type of surgical resection in tumours ≤5 cm distant from the anal verge (p = 0.14). Pathological complete response was achieved in 16 % of the patients in the pre-CRT group. The local recurrence rate (LRR) at 5 years was 5.7 % in the pre-CRT and 11.1 % in the post-CRT groups (p = 0.04). The distant recurrence rate (DRR) at 5 years was 76 % and 77 % in the pre-CRT and post-CRT groups, respectively (p = 0.1). Overall survival was similar in two groups (74.8 % vs. 75.3 %, p = 0.3).

CONCLUSIONS

The treatment of stage T3, N0 rectal cancer patients with pre-CRT followed by surgery decreased LRR, but did not improve DRR or OS as compared with surgery followed by post-CRT in our patient cohort.

Current controversies in neoadjuvant chemoradiation of rectal cancer

Total mesorectal excision with preoperative radiation and chemotherapy provide the lowest local recurrence rates for rectal cancer. Timing of surgery after preoperative chemoradiation is being increased to optimize tumor downstaging. In cases of complete clinical response from chemoradiation, permissive observation without resection is being investigated. Significant anorectal dysfunction results from low anterior resection and radiation. Good prognostic tumor characteristics are being investigated with the aim of selecting cases for whom preoperative radiation may be avoided. Preoperative and postoperative radiation provides improved local cancer control for superficial cancers removed by local excision.

Expression and prognostic relevance of tumor carcinoembryonic antigen in stage IB non-small cell lung cancer

BACKGROUND

High serum carcinoembryonic antigen (CEA) levels have been reported to be associated with poor prognosis in non-small cell lung cancer (NSCLC), while the prognostic role of tumor CEA expression remains to be defined. The present study investigated the expression of tumor CEA in stage IB NSCLC, and correlated it with clinicopathological features and prognosis.

PATIENTS AND METHODS

Immunohistochemistry for tumor CEA was assessed in the specimens of 183 patients with stage IB NSCLC. Receiver-operating characteristic (ROC) curve analysis was used to determine the cut-off score for tumor positivity.

RESULTS

High CEA expression was detected more frequently in adenocarcinomas (72.2%) and other NSCLCs (69.0%) than in squamous cell carcinomas (25.4%, P<0.001). Both univariate and multivariate analysis indicated that tumor CEA was an independent prognostic factor for overall and disease-free survival (P<0.05).

CONCLUSIONS

Elevated expression of tumor CEA may be an adverse prognostic indicator in stages IB NSCLC.

Treatment of locally advanced rectal cancer: Controversies and questions

Rectal cancers extending through the rectal wall, or involving locoregional lymph nodes (T3/4 or N1/2), have been more difficult to cure. The confines of the bony pelvis and the necessity of preserving the autonomic nerves makes surgical extirpation challenging, which accounts for the high rates of local and distant relapse in this setting. Combined multimodality treatment for rectal cancer stage II and III was recommended from National Institute of Health consensus. Neoadjuvant chemoradiation using fluoropyrimidine-based regimen prior to surgical resection has emerged as the standard of care in the United States. Optimal time of surgery after neoadjuvant treatment remained unclear and prospective randomized controlled trial is ongoing. Traditionally, 6-8 wk waiting period was commonly used. The accuracy of studies attempting to determine tumor complete response remains problematic. Currently, surgery remains the standard of care for rectal cancer patients following neoadjuvant chemoradiation, whereas observational management is still investigational. In this article, we outline trends and controversies associated with optimal pre-treatment staging, neoadjuvant therapies, surgery, and adjuvant therapy.

Do all locally advanced rectal cancers require radiation? A review of literature in the modern era

Potentially curable rectal cancer is primarily treated with surgical resection. Adjuvant or neoadjuvant radiotherapy is often utilized for patients deemed to be at unacceptable risk for local recurrence. The purpose of this article is to review the pertinent literature and elucidate the role of radiotherapy in patients with an intermediate risk of local recurrence. The addition of chemoradiotherapy is recommended in the majority of patients with transmural or node positive rectal cancer. However, some patients with favorable characteristics may have only a small incremental benefit from the addition of radiotherapy. The decision to treat or not to treat should take into consideration the patient and physician tolerance of risk of recurrence and risk of treatment related toxicity. The primary factors identified for determining low risk patients are circumferential radial margin (CRM), location within the rectum, and nodal status. Patients at lowest risk have widely negative CRM (>2mm), proximal lesions (>10cm from the anal verge), and no nodal disease. Patients with all three low risk factors have an absolute reduction in local recurrence that is <5% and may be eligible to forego radiotherapy. Additional factors identified which may impact local recurrence risk are elevated serum CEA level, lymphovascular space invasion, pathologic grade, and extramural space invasion.

T3N0 rectal cancer: radiation for all?

The optimal oncologic management for patients with T3N0 rectal cancer is currently controversial. Patients with pathologic T3N0 disease may have an "intermediate" risk of disease recurrence, suggesting that perhaps trimodality therapy may not be indicated for all patients. Adverse prognostic features, including a greater depth of perirectal fat invasion, poor tumor differentiation, the presence of lymphovascular invasion, abnormally elevated pretreatment carcinoembryonic antigen levels (>5 ng/mL), circumferential margin involvement, and a low-lying position may identify T3N0 patients at high risk for local recurrence who may benefit from the addition of radiation therapy. However, recent randomized data suggest an improvement in local control and disease-free survival with preoperative radiation therapy compared with selective postoperative radiation therapy in all patient subgroups, arguing in favor of routine preoperative therapy. Additionally, rates of clinical understaging may exceed 20%, representing the percentage of patients who would require the delivery of postoperative radiotherapy with its associated sequelae. Future prospective randomized studies of T3N0 patients with upfront stratification by known prognostic factors and studies evaluating the molecular profile of rectal cancers hold the promise of better classifying patients at high risk of local and systemic recurrence, and thus, in need of adjuvant radiation and chemotherapy.

Neoadjuvant treatment in rectal cancer: actual status

Neoadjuvant (preoperative) concomitant chemoradiotherapy (CRT) has become a standard treatment of locally advanced rectal adenocarcinomas. The clinical stages II (cT3-4, N0, M0) and III (cT1-4, N+, M0) according to International Union Against Cancer (IUCC) are concerned. It can reduce tumor volume and subsequently lead to an increase in complete resections (R0 resections), shows less toxicity, and improves local control rate. The aim of this review is to summarize actual approaches, main problems, and discrepancies in the treatment of locally advanced rectal adenocarcinomas.

Clinical impact of lymph node status in rectal cancer

Lymph node status at the time of diagnosis remains one of the principal indicators of prognosis in patients with rectal cancer. Involvement of loco-regional lymph nodes is relevant to surgical and clinical oncologists and continues to impact significantly upon local and systemic management strategies, in both neo-adjuvant and adjuvant settings. In this review, the clinical impact of lymph node status in the surgical management of rectal cancer is considered, with particular reference to the significance of lymphadenectomy and the potential implications for rectal tumours amenable to trans-anal excision. Current standards of care are reviewed and the extent to which the determination of lymph node status influences oncological decisions regarding neo-adjuvant and adjuvant therapies are discussed with areas of controversy highlighted.

Perineural invasion in pT3N0 rectal cancer: the incidence and its prognostic effect

BACKGROUND

The authors' purpose was to explore the incidence and prognostic significance of perineural invasion (PNI) in pT3N0 rectal cancer.

METHODS

Pathologic materials from resected specimens of 173 patients with pT3N0 rectal cancer were retrospectively collected. PNI-positivity was categorized into 2 groups: surrounding the nerve sheath (SS-PNI) and invading through the nerve sheath (TS-PNI). The rate of PNI-positivity was compared with PNI as initially recorded in the original reports. Patients' outcome was studied in groups with different PNI status, and multivariate analysis was performed to determine its prognostic value.

RESULTS

In this retrospective analysis, PNI-positivity was found in 24.3% of all cases, in which SS-PNI and TS-PNI were 11% and 13.3%, respectively, and was related to lymphovascular invasion. Only 7.5% of patients' specimens were reported as PNI-positive in the original reports. Detection of SS-PNI was likelier to be missed than TS-PNI. The rates of local recurrence, disease-free survival, and overall survival at 5 years were similar between the groups of SS-PNI and TS-PNI. The 5-year local recurrence rate was more than 2.5-fold higher in the PNI-positive group compared with the PNI-negative group (22.7% vs 7.9%, respectively; P = .017). Multivariate analysis proved that PNI-positivity was the only independent risk factor for predicting 5-year local recurrence rate, whereas only sampled lymph nodes was related to 5-year disease-free survival and overall survival.

CONCLUSIONS

PNI is a common pathologic feature in rectal cancer. The definition of PNI should include SS-PNI and TS-PNI. Rectal cancer patients who are PNI-positive are at higher risk of local recurrence and should be considered for more intensive treatment.

Do all locally advanced rectal cancers require radiation? A review of literature in the modern era

Potentially curable rectal cancer is primarily treated with surgical resection. Adjuvant or neoadjuvant radiotherapy is often utilized for patients deemed to be at unacceptable risk for local recurrence. The purpose of this article is to review the pertinent literature and elucidate the role of radiotherapy in patients with an intermediate risk of local recurrence. The addition of chemoradiotherapy is recommended in the majority of patients with transmural or node positive rectal cancer. However, some patients with favorable characteristics may have only a small incremental benefit from the addition of radiotherapy. The decision to treat or not to treat should take into consideration the patient and physician tolerance of risk of recurrence and risk of treatment related toxicity. The primary factors identified for determining low risk patients are circumferential radial margin (CRM), location within the rectum, and nodal status. Patients at lowest risk have widely negative CRM (>2mm), proximal lesions (>10cm from the anal verge), and no nodal disease. Patients with all three low risk factors have an absolute reduction in local recurrence that is <5% and may be eligible to forego radiotherapy. Additional factors identified which may impact local recurrence risk are elevated serum CEA level, lymphovascular space invasion, pathologic grade, and extramural space invasion.